Chimpanzees are significantly smaller than adult humans, yet they are mind-blowingly stronger than a human. Just because something is small doesn't mean it can't be strong. If it has the capacity to effectively use deadly weapons (which act as a force multiplier) then it is even more dangerous. A goblin or kobold does not necessarily have the same muscle strength as a human relative to their size.
We have stats for baboons, at least in certain editions. They don't deal only 1 damage. A chimp is stronger than a baboon, so it would deal even more damage.
However, I was clearly talking about a toddler with a stick.
And I'm talking about creatures that
actually deal 1 damage, which is the only number that matters in any discussion of minions.
If the soldier had 8 HP instead of 1, and the PC fighting him had an 8 damage minimum (roll of 1 + 5 attribute mod + 2 sneak attack dice) then there's no discernable difference between whether he's a minion or just a low HP creature. He dies from one hit either way. You're suggesting that it's somehow problematic if he was a minion in this hypothetical, despite the outcomes being identical?
If he was a minion, he never would have survived long enough to encounter the PC in the first place, especially while training to become a soldier. He would have suffered some injury at some point, of sufficient severity that a finite number of them would result in death. And if he's a minion, then any amount of quantifiable damage will instantly result in irrevocable death. Minions are entirely incapable of being non-fatally wounded, or of healing, or of being beaten into unconscious (with the possible exception of a deliberate attack by someone attempting to spare their life).
If we're only concerned with this soldier's interaction with the PC, then 1hp is sufficiently similar to 8hp
iff the PC cannot possibly deal less than 8 damage with a hit, which is never guaranteed to be the case. It's certainly possible for almost any PC to deal less than 8 damage with an attack, regardless of level. Maybe they're throwing a rock. Maybe they're de-buffed, or the minions are buffed, or other situational modifiers are in effect.
Moreover, if we do pretend that it's reasonable to assume any PC of a given level will deal at least 8 damage with an attack, then why not model those minions as having 8hp? It would solve almost every complaint, while being virtually identical in play (according to your argument). The only possible explanation I can see is that they were intentionally trying to alienate any potential player who wanted to take the game seriously; in which case, mission accomplished.